数据结构

#include 
#include 
#include 
typedef int elemType;
//链栈节点（链栈的存储结构）
typedef struct StackNode
{
	elemType data;
	struct StackNode* next;
}stackNode;

int Push(stackNode * S,elemType e)  //头插法
{
	stackNode* p = (stackNode*)malloc(sizeof(stackNode));
	if (p == NULL)
	{
		printf("内存申请失败n");
		return -1;
	}
	p->data = e;
	p->next = S->next;
	S->next = p;
	return 0;
}

int Pop(stackNode* S)
{
	if (S == NULL || S->next == NULL)
	{
		puts("链栈为空!n");
		return -1;
	}
	stackNode* p = S->next; //用指针变量p临时保存栈顶元素空间，以备释放
	S->next = S->next->next;
	free(p);
	return 0;
}

void stackTraverse(stackNode* S)
{
	printf("n遍历链栈：");
	if (S == NULL || S->next == NULL)
	{
		puts("链栈为空!n");
		return ;
	}
	stackNode* p = S->next;
	while (p != NULL)
	{
		printf("%d ",p->data);
		p = p->next;
	}
	printf("n");
}

elemType GetTop(stackNode* S)
{
	if (S == NULL || S->next == NULL)
	{
		puts("链栈为空!n");
		return -1;
	}
	return S->next->data;
}

int main()
{
	//创建栈的表头节点（空节点）
	stackNode Q;
	stackNode* S = &Q;
	S->data = 0;
	S->next = NULL;
	
	//向链栈赋值
	printf("向链栈赋值(以空格分开，输入0结束):n");
	int n = 0;
	scanf_s("%d",&n);
	while (n != 0)   //输入0表示输入结束
	{
		Push(S, n);
		scanf_s("%d", &n);
	}

	stackTraverse(S);
	printf("n栈顶元素为：%dn", GetTop(S));

	Pop(S);
	printf("删除栈顶元素之后的链栈：");
	stackTraverse(S);
	printf("n栈顶元素为：%dn", GetTop(S));

	return 0;
}